JP2014228276A - Particle detection device and particle detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a particle detection device capable of accurately detecting a particle.SOLUTION: The particle detection device includes: an enclosure 1; a chamber 2 disposed inside the enclosure 1; an introduction nozzle 21 provided in the chamber 2; a sample introduction path 3 which connects a first introduction port 11 provided in the enclosure 1 and the introduction nozzle 21 provided in the chamber 2 and introduces a fluid including particles into the chamber 2; an adjustment mechanism 5 which supplies the fluid from which particles have been removed, into the chamber 2 via an adjustment path 4 communicating with the chamber 2 through a second introduction port 12 different from the first introduction port 11 provided in the enclosure 1 and which adjusts the state of the fluid in the chamber 2; and a detection mechanism 23 which irradiates the fluid jetted from the introduction nozzle 21 with light to detect particles included in the fluid.

Description

  The present invention relates to an environment evaluation technique, and more particularly to a particle detection apparatus and a particle detection method.

  In a general indoor room or a clean room such as a bio clean room, a particle detection device may be used to detect or record particles containing scattered microorganisms (for example, Patent Documents 1 and 2 and non-patent documents). Reference 1). The optical particle detection device, for example, sucks a gas in a room where the device is arranged and irradiates the sucked gas with light. If the gas contains particles, the light-irradiated particles emit fluorescence or generate scattered light, so it is possible to detect the number and size of the particles contained in the gas. .

JP 2008-225539 A JP 2011-83214 A

Hasegawa, M. et al., “Real-time microorganism detection technology in the air and its application”, Yamatake Corporation, azbil Technical Review December 2009, p.2-7, 2009

  An object of the present invention is to provide a particle detection apparatus and a particle detection method capable of accurately detecting particles.

  According to an aspect of the present invention, (a) a housing, (b) a chamber disposed inside the housing, and (c) particles are contained in the chamber from the first inlet provided in the housing. Particles are removed into the chamber through a sample introduction path for introducing a fluid and (d) an adjustment path communicating with the chamber from a second inlet different from the first inlet provided in the housing A particle detection mechanism, comprising: an adjustment mechanism for supplying the measured fluid and adjusting a state of the fluid in the chamber; and (e) a detection mechanism for irradiating the fluid in the chamber with light and detecting particles contained in the fluid An apparatus is provided.

  According to the aspect of the present invention, (a) a fluid containing particles is introduced from a first introduction port provided in the casing into a chamber disposed inside the casing through the sample introduction channel. And (b) supplying a fluid from which particles have been removed into the chamber through an adjustment path communicating with the chamber from a second inlet different from the first inlet provided in the housing, There is provided a particle detection method comprising: adjusting a state of the fluid in the chamber; and (c) irradiating the fluid in the chamber with light to detect particles contained in the fluid.

  ADVANTAGE OF THE INVENTION According to this invention, the particle | grain detection apparatus and particle | grain detection method which can detect particle | grains correctly can be provided.

It is a schematic diagram of the particle | grain detection apparatus which concerns on the 1st Embodiment of this invention. It is a schematic diagram of the particle | grain detection apparatus which concerns on the comparative example of this invention. It is a schematic diagram of the particle | grain detection apparatus which concerns on the 2nd Embodiment of this invention.

  Embodiments of the present invention will be described below. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, the drawings are schematic. Therefore, specific dimensions and the like should be determined in light of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

(First embodiment)
As shown in FIG. 1, the particle detection apparatus according to the first embodiment includes a housing 1, a chamber 2 disposed inside the housing 1, an introduction nozzle 21 provided in the chamber 2, and a housing. A sample introduction path 3 for introducing a fluid containing particles into the chamber 2, which connects the first introduction port 11 provided in the body 1 and the introduction nozzle 21 provided in the chamber 2, is provided in the housing 1. The fluid from which the particles have been removed is supplied into the chamber 2 through the adjustment path 4 communicating with the chamber 2 from the second inlet 12 different from the first inlet 11, An adjustment mechanism 5 that adjusts the state of the fluid, and a detection mechanism 23 that irradiates the fluid ejected from the introduction nozzle 21 with light and detects particles contained in the fluid.

  The shape of the housing 1 is arbitrary. As a material of the housing 1, metal, resin, and the like can be used, but are not limited thereto. The shape and material of the chamber 2 are arbitrary. However, the chamber 2 preferably has pressure resistance. The sample introduction path 3 includes a pipe made of, for example, metal and resin.

  A discharge nozzle 22 is provided in the chamber 2 so as to face the introduction nozzle 21. Further, the housing 1 is further provided with a discharge port 13 for discharging the fluid in the chamber 2 connecting the discharge nozzle 22 of the chamber 2 and the discharge port 13 of the housing 1 to the outside of the housing 1. The discharge path 6 is provided. The discharge path 6 includes a pipe made of, for example, metal and resin. The exhaust path 6 is provided with an exhaust pump 62 as an exhaust fan.

  A fluid such as gas outside the housing 1 sucked from the first introduction port 11 of the housing 1 by the exhaust air pump 62 is ejected into the chamber 2 through the sample introduction path 3 and the introduction nozzle 21. The fluid ejected into the chamber 2 is discharged from the chamber 2 through a discharge nozzle 22 provided facing the introduction nozzle 21, and further from a discharge port 13 provided in the case 1 through a discharge path 6. 1 is discharged to the outside.

  The detection mechanism 23 irradiates light to a fluid flow such as an air flow formed between the introduction nozzle 21 and the discharge nozzle 22 and detects the number of particles by detecting, for example, scattered light generated by particles contained in the fluid. Is detected. Alternatively, the detection mechanism 23 detects the number of particles contained in the fluid introduced into the chamber 2 from the first introduction port 11 by detecting fluorescence emitted by the particles contained in the fluid. Further, the detection mechanism 23 calculates the concentration of particles in the fluid by dividing the number of particles detected per unit time by the volume of the fluid sucked from the first inlet 11 per unit time.

  Here, the particles include biological substances including microorganisms, chemical substances, dust, dust, and dust such as dust. Examples of microorganisms include bacteria and fungi. Examples of bacteria include gram negative bacteria and gram positive bacteria. Examples of gram-negative bacteria include E. coli. Examples of Gram positive bacteria include Staphylococcus epidermidis, Bacillus subtilis, Micrococcus, and Corynebacterium. Examples of fungi include Aspergillus such as black mold. However, the microorganism is not limited to these.

  If the fluid contains fluorescent particles such as microorganisms, the particles emit light when irradiated with light. For example, riboflavin, flavin nucleotide (FMN), flavin adenine dinucleotide (FAD), nicotinamide adenine dinucleotide phosphate (NAD (P) H), pyridoxamine, pyridoxal phosphate (pyridoxal) contained in microorganisms -5'-phosphate, pyridoxine, tryptophan, tyrosine, phenylalanine, and the like emit fluorescence.

  For example, when the particle detection device is arranged in a clean room or the like, it may not be preferable that particles are contained in the fluid discharged from the discharge port 13 provided in the case 1 to the outside of the case 1. In this case, an exhaust air filter 61 such as a HEPA filter (High Efficiency Particulate Air Filter) may be provided in the exhaust path 6.

  In the introduction nozzle 21 of the chamber 2, the cross-sectional area of the fluid is reduced, the flow rate increases, and the pressure decreases. Therefore, convection may occur around the fluid flow formed between the introduction nozzle 21 and the discharge nozzle 22. In addition, due to the pressure in the chamber 2 decreasing, fluid may not be smoothly discharged from the discharge nozzle 22. When convection occurs in the chamber 2 or the pressure in the chamber 2 decreases, particles can stay inside the chamber 2. If particles stay in the chamber 2, the detection mechanism 23 can detect the same particle a plurality of times, so that it may be difficult to accurately detect the number of particles contained per volume of the fluid.

  On the other hand, the particle detection apparatus according to the first embodiment has an adjustment path 4 that communicates with the chamber 2 from a second introduction port 12 different from the first introduction port 11 provided in the housing 1. The fluid from which particles have been removed is supplied to the chamber 2 through the pressure, the pressure in the chamber 2 is increased, the fluid in the chamber 2 is rectified, and the state of the fluid in the chamber 2 is adjusted. An adjustment mechanism 5 is provided. Thereby, it is possible to smoothly discharge the fluid containing particles from the discharge nozzle 22.

  The adjustment path 4 includes a pipe made of, for example, metal and resin. In the adjustment path 4, for example, a first filter 51, an adjustment pump 52, a flow meter 53, and a second filter 54 are provided. Particles contained in the fluid outside the housing 1 sucked from the second inlet 12 by the adjustment pump 52 are removed by the first filter 51 and the second filter 54. The flow meter 53 measures the flow rate such as the volume of the fluid from which particles are removed, which is supplied to the chamber 2 by the adjustment pump 52 per unit time, for example.

  Here, in the reference example of the present invention, as shown in FIG. 2, the housing 1 is provided with a single inlet 111, and the common path 103 connected to the single inlet 111 is adjusted to The adjustment path 104 of the mechanism 105 and the sample introduction path 3 are connected. The adjustment pump 152 sucks a part of the fluid from the common path 103 to the adjustment path 104, and particles contained in the sucked fluid are removed by the first filter 151 and the second filter 154. The fluid from which the particles have been removed is supplied to the chamber 2 in order to adjust the pressure in the chamber 2 by pressurizing or the like.

  The detection mechanism 123 calculates the concentration of particles in the fluid by dividing the number of particles detected per unit time by the volume of the fluid sucked into the sample introduction path 3 per unit time. For example, 40 L of fluid per unit time is sucked from a single inlet 111, 10 L of fluid is distributed to the adjustment path 104 at the branch point 200, and 30 L of fluid is distributed to the sample introduction path 3. . In this case, the detection mechanism 123 calculates the concentration of particles by dividing the number of particles detected per unit time by 30 L that is the volume of the fluid distributed to the sample introduction path 3.

  However, the ratio of the number of particles toward the adjustment path 104 and the number of particles toward the sample introduction path 3 at the branch point 200 is not necessarily limited to the volume of the fluid distributed to the adjustment path 104 and the sample introduction path 3. Does not match the ratio of the volume of fluid dispensed into the. For example, when 10 L of fluid per unit time is distributed to the adjustment path 104 and 30 L of fluid per unit time is distributed to the sample introduction path 3, the volume of the fluid distributed to the adjustment path 104 and the sample introduction path The ratio of the volume of fluid distributed to 3 is 1: 3. However, when the common path 103 and the sample introduction path 3 are arranged on a straight line at the branch point 200, particles tend to flow more to the sample introduction path 3 than the adjustment path 104 due to inertial force. is there. For this reason, it is possible to calculate the concentration of particles in the fluid by dividing the number of particles detected by the detection mechanism 123 by the volume of the fluid distributed to the sample introduction path 3, and that the concentration may be higher than the actual concentration. Found.

  On the other hand, in the particle detector according to the first embodiment shown in FIG. 1, the adjustment path 4 is not branched from the sample introduction path 3, and the fluid used for adjusting the pressure in the chamber 2 is Suction is performed from a second introduction port 12 different from the first introduction port 11 provided in the body 1. Therefore, since the adjustment path 4 is independent of the sample introduction path 3 and the adjustment path 4 is not branched from the sample introduction path 3, the number of particles detected per unit time by the detection mechanism 123 is An error does not occur even if the concentration of particles in the fluid is calculated by dividing the volume of the fluid sucked from the first inlet 11 per unit time and flowing through the sample introduction path 3. Therefore, according to the particle detection apparatus according to the first embodiment, the number and concentration of particles contained in the fluid can be accurately detected.

(Second Embodiment)
As shown in FIG. 3, the adjustment mechanism 5 of the particle detector according to the second embodiment includes a compressor 55 that compresses a gas as a fluid. The compressed gas as the pressurized fluid sent out from the compressor 55 is sent into the chamber 2 through the first filter 51, the pressure regulator 56, the control valve 57, and the second filter 54. The first filter 51, the pressure regulator 56, the control valve 57, and the second filter 54 are provided in the adjustment path 4 that passes through the second introduction port 12.

  A bypass path 71 branches off from a portion 70 between the pressure regulator 56 and the control valve 57 of the adjustment path 4, and the bypass path 71 merges with the discharge path 6. The first filter 51 and the second filter 54 remove particles contained in the compressed gas. The pressure regulator 56 adjusts the pressure of the compressed gas supplied into the chamber 2. The control valve 57 adjusts the distribution ratio of the compressed gas distributed to the adjustment path 4 and the bypass path 71.

  An ejector 63 is disposed at the junction of the bypass path 71 and the discharge path 6. When the compressed gas is supplied from the bypass path 71 to the ejector 63, the ejector 63 sucks the fluid in the chamber 2. According to the particle detector according to the second embodiment, the compressor 55 can perform both supply of compressed gas into the chamber 2 and exhaust from the chamber 2. Energy consumption can be reduced.

(Other embodiments)
Although the present invention has been described by the embodiments as described above, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques should be apparent to those skilled in the art. For example, the detection mechanism 23 shown in FIGS. 1 and 3 may calculate the aerodynamic diameter of a particle by measuring the time of flight of the particle passing between two laser beams. Thus, it should be understood that the present invention includes various embodiments and the like not described herein.

DESCRIPTION OF SYMBOLS 1 Housing | casing 2 Chamber 3 Sample introduction path | route 4 Adjustment path | route 5 Adjustment mechanism 6 Discharge path | route 11 1st introduction port 12 2nd introduction port 13 Discharge port 21 Introduction nozzle 22 Discharge nozzle 23 Detection mechanism 51 1st filter 52 Adjustment Pump 53 Flow meter 54 Second filter 55 Compressor 56 Pressure regulator 57 Control valve 61 Exhaust filter 62 Exhaust pump 63 Ejector 70 Part 71 Bypass path 103 Common path 104 Adjustment path 105 Adjustment mechanism 111 Inlet 123 Detection mechanism 151 First filter 152 Regulating pump 154 Second filter 200 Branch point

Claims (18)

A housing,
A chamber disposed within the housing;
A sample introduction path for introducing a fluid containing particles into the chamber from a first introduction port provided in the housing;
A fluid from which particles have been removed is supplied into the chamber from a second introduction port different from the first introduction port provided in the housing via an adjustment path communicating with the chamber. An adjustment mechanism for adjusting the fluid state of
A detection mechanism for irradiating the fluid in the chamber with light and detecting particles contained in the fluid;
A particle detector.   The particle detection apparatus according to claim 1, wherein the detection mechanism detects the number of particles per volume of fluid introduced into the chamber from the first introduction port. The adjustment mechanism is
A regulating pump for supplying the fluid into the chamber;
A filter for removing particles contained in the fluid;
The particle | grain detection apparatus of Claim 1 or 2 provided with these. An introduction nozzle provided in the chamber and connected to the sample introduction path;
A discharge nozzle provided in the chamber facing the introduction nozzle;
A discharge path for discharging the fluid in the chamber to the outside of the casing, connecting the discharge port provided in the casing and the discharge nozzle;
The particle | grain detection apparatus of any one of Claim 1 thru | or 3 further equipped with these. A bypass path that branches off from the adjustment path and joins the discharge path;
An ejector is disposed at the junction of the bypass path and the discharge path,
The particle detection apparatus according to claim 4, wherein the ejector sucks the fluid in the chamber by supplying pressurized fluid from the bypass path to the ejector.   The particle detection apparatus according to claim 1, wherein the adjustment mechanism adjusts the pressure in the chamber.   The particle detection apparatus according to claim 1, wherein the adjustment mechanism rectifies the inside of the chamber.   The particle detection apparatus according to claim 1, wherein the detection mechanism detects scattered light generated in the particles.   The particle detection apparatus according to claim 1, wherein the detection mechanism detects fluorescence emitted by the particles. Introducing a fluid containing particles into a chamber disposed inside the casing through a sample introduction path from a first inlet provided in the casing;
A fluid from which particles have been removed is supplied into the chamber from a second introduction port different from the first introduction port provided in the housing via an adjustment path communicating with the chamber. Adjusting the fluid state of the
Irradiating the fluid in the chamber with light to detect particles contained in the fluid;
A method for detecting particles, comprising:   The particle detection method according to claim 10, wherein in detecting particles contained in the fluid, the number of particles per volume of the fluid introduced into the chamber from the first introduction port is detected. In supplying the fluid from which particles have been removed into the chamber via the adjustment path, an adjustment pump is used,
The adjustment path is provided with a filter for removing the particles,
The method for detecting particles according to claim 10 or 11. The chamber is provided with an introduction nozzle connected to the sample introduction path;
The fluid in the chamber is discharged to the outside of the casing through a discharge path connecting a discharge nozzle provided in the chamber so as to face the introduction nozzle and a discharge port provided in the casing. The particle detection method according to claim 10, further comprising: Supplying pressurized fluid to a bypass path branched from the adjustment path and joined to the discharge path via an ejector;
The ejector aspirates fluid in the chamber;
The particle detection method according to claim 13, further comprising:   The particle detection method according to claim 10, wherein the pressure in the chamber is adjusted in adjusting the state of the fluid in the chamber.   The particle detection method according to any one of claims 10 to 15, wherein the inside of the chamber is rectified by adjusting a state of a fluid in the chamber.   The particle detection method according to claim 10, wherein in detecting the particle, scattered light generated in the particle is detected.   The particle detection method according to claim 10, wherein in detecting the particle, fluorescence emitted from the particle is detected.